A new mutation in the gene ROR2 causes brachydactyly type B1

• We repot a three-generation Chinese family with dominant inheritance BDB1.
• A novel mutation c.1396-1398delAA in the gene ROR2 was detected in this family.
• The mutation is predicted to produce a truncated protein with a new polypeptide.

Brachydactyly type B, an autosomal dominant disorder that is characterized by hypoplasia of the distal phalanges and nails, can be divided into brachydactyly type B1 (BDB1) and brachydactyly type B2 (BDB2). BDB1 is caused by mutations in the receptor tyrosine kinase gene ROR2, which maps to chromosome 9q22, whereas BDB2 is caused by point mutations in the bone morphogenetic protein antagonist NOGGIN. Here, we report a three-generation Chinese family with dominant inheritance of the BDB1 limb phenotype. Sequence analysis identified a novel heterozygous base deletion (c.1396–1398delAA) in the gene ROR2 in all affected family members. This new deletion is expected to produce a truncated Ror2 protein with a new polypeptide of 57 amino acids at the C-terminal.